Chapter 5 - Prehistoric Archaeological Resources: Evaluation and Treatment

At least 12,000 years of human occupation are represented in California's prehistoric archaeological sites. These resources form an irreplaceable source of knowledge of the prehistoric events, peoples, and lifeways of the region. Increasingly, however, growth and development have threatened the existence of that archaeological record which, once lost, can never be restored. By enacting a body of law and by providing regulations and guidelines, both the federal and state governments have taken steps to protect those non-renewable resources.

Caltrans cultural resource policy is to avoid and, if avoidance is not possible, to minimize adverse effects of transportation projects upon significant cultural resources. This chapter provides information on the procedures and documents used to implement this policy and to comply with state and federal laws and regulations, with respect to prehistoric archaeological resources; see Chapter 6 for guidance on historical archaeological resources.

Caltrans prepares cultural resources studies to comply with the California Environmental Quality Act of 1970 (CEQA) and Section 106 of the National Historic Preservation Act (NHPA) of 1966, as amended. Chapter 2 discusses the general regulatory context of this work. Chapter 3 discusses laws relating to the involvement of Native American Tribes, groups or individuals in cultural resource studies.

Consistent with the requirements of NHPA Section 304, the Federal Highway Administration (FHWA), and Caltrans acting on its behalf, may withhold from disclosure to the public all information relating to the location or character of historic properties whenever they determine that disclosure may create a substantial risk of harm to the resource.

Information on archaeological site locations is also exempt from public access, as provided by the California Public Records Act (California Government Code 6254.10).

Caltrans selects cultural resources specialists based on standards set by the California State Personnel Board and the federal Secretary of the Interior’s Professional Qualifications Standards. While these different standards overlap in many regards, they are not identical. Taking into consideration these different sets of standards in relation to Caltrans cultural resources needs, Caltrans has identified six levels of archaeological qualifications for Caltrans cultural resources staff. These six levels are codified as Professionally Qualified Staff (PQS) levels in the Section 106 Programmatic Agreement (Section 106 PA) Attachment 1 (see Exhibit 1.1), and have been adopted as the new qualifications standards for both federal undertakings and state-only (Section 106 and CEQA-level) Caltrans cultural resources activities. These qualifications levels are as follows:

• Archaeological Crew Member
• Lead Archaeological Surveyor
• Co-Principal Investigator, Prehistoric Archaeology
• Co-Principal Investigator, Historical Archaeology
• Principal Investigator, Prehistoric Archaeology
• Principal Investigator, Historical Archaeology

These levels and associated criteria are specific to Caltrans, and may or may not correspond with similar titles and qualifications in other agencies and organizations. The six qualifications levels reflect increasing levels of expertise, as demonstrated by education, experience, understanding of the Section 106 process, and familiarity with Caltrans’ cultural resource policies, procedures, and goals. Use of these qualifications levels is designed to provide a credible and competent staff, and to ensure that Caltrans staff meets the standards of the federal agencies that review Caltrans’ work. All Caltrans archaeological work must be performed by and/or, directed and reviewed, by Professionally Qualified Staff, or PQS (i.e., staff meeting the qualifications for the designated level of work).

The Section 106 PA Attachment 1 lists the criteria to meet these different qualification levels. Caltrans archaeological staff are certified as to level of expertise by submitting a completed copy of the relevant PQS certification form to the Headquarters’ Cultural and Community Studies Office (CCSO) of the Division of Environmental Analysis (DEA) for evaluation by the CCSO Chief. (See Chapter 1 for a complete discussion on the subject of qualifications). Exhibit 1.5 Table 2 provides a chart of PQS levels required for roles in archaeological studies.

Caltrans also uses the same professional qualifications standards in fulfilling its cultural resources compliance for prehistoric archaeology under other laws and regulations.

Caltrans staff archaeologists

Consultant archaeologists

Later sections of this chapter discuss the standards for completing and evaluating various Caltrans archaeological studies and documents. These standards are based primarily on the standards set forth at 36 CFR §800.11, but also rely on guidance in the Secretary of Interior's Standards and Guidelines for Archeology and Historic Preservation, and the California Office of Historic Preservation (OHP) publications Archaeological Resource Management Reports (ARMR): Recommended Contents and Format (DPR 1989) and Guidelines for Archaeological Research Designs (DPR 1991).

Information on the specific locations of archaeological sites are made available only on a "need-to-know" basis to individuals who legitimately need this information to meet their project responsibilities. This may include Caltrans environmental branch chiefs and generalists, project managers and engineers, archaeological consultants, and Native American Tribes, groups or individuals.

As a general rule, archaeological site records, maps, and aerials depicting exact site locations are limited to technical documents, such as archaeological survey and excavation reports. These documents are not available to the general public, but qualified researchers may consult them at the District Environmental Branch (DEB), CCSO, and the Information Centers of the California Historical Resources Information System (CHRIS). The Information Centers require all researchers who use the records to sign an Agreement of Confidentiality form which states that they will not disclose specific site locations to unauthorized individuals or in publicly distributed documents without written consent of the State Historic Preservation Officer (SHPO).

While management documents, such as Historic Property Survey Reports (HPSR), may need to extract information from technical documents, such documents are to exclude sensitive materials.

The amount of staff work and schedule time required to complete the different types of archaeological studies vary greatly, depending on a range of potentially important factors:

• Size of the project.
• Number and complexity of the sites involved.
• Changes in project schedules or design.
• Delays in ancillary studies.
• Conflicting workload priorities.

Caltrans has made several analyses of projects to provide rough estimates for work and schedule requirements. Exhibit 2.3 summarizes these estimates which can range from one month for a survey report to as much as five years for a project requiring data recovery excavations.

The CCSO provides archaeological assistance to the Districts when requested. This assistance includes providing staff for surveys, remote sensing, excavations, other fieldwork, consultant monitoring, and laboratory work, report writing, and peer review of reports. To request assistance the District Environmental Branch Chief (DEBC) sends a memo to the appropriate CCSO Branch Chief. Chapter 1 Section 1-3.2 of this handbook describes the CCSO branches and their functions. The request memo should state:

• The type of assistance needed.
• Basic information on the highway project, including county, route, post miles, and expenditure authorization.
• Project maps showing the project's location and limits.
• District contacts for the project, including the project manager, project engineer, and environmental generalist.
• Target date for completion of the requested service.
• Priority status of the proposed project in relation to other assistance work being done by CCSO for the District.

Caltrans' policy is that "no field activity shall be considered so important or urgent that…any safe practice will be compromised." The lead archaeologist on a field crew is responsible for ensuring that the crew is aware of safety hazards, concerns, and precautions. Chapter 4 and Exhibit 2.6 provide more information on field safety.

For work in remote or dangerous localities and in hazardous areas or conditions, safety procedures include the "buddy system" on surveys and daily communication with a supervisor. Where applicable, staff should be certified in Hazardous Waste Operations and Emergency Response (40-HAZWOPER) safety training, confined space procedures, and shoring procedures. For excavations deeper than 150 cm (5 ft.), shoring, or acceptable alternatives to shoring, in conformity with the Division of Occupational Safety and Health (OSHA) standards, must be used. The principal investigator on excavations can also request a safety review by the District Safety Officer.

Additional information on safety practices can be found in:

• Caltrans Safety Manual, Chapter 11, “Code of Safe Work Practices.”
• Caltrans Construction Manual, Chapter 2, "Safety and Traffic."
• Caltrans Survey Manual, Chapter 2,“Safety.” See relevant excerpts from this handbook in Exhibit 2.6.

The identification phase for archaeological studies typically involves conducting a records search, continuing consultation with Native Americans, conducting an archaeological field survey of the project Area of Potential Effects (APE), and documenting the results of the survey (both prehistoric and historical archaeological properties) in an Archaeological Survey Report (ASR), discussed in Section 5-4.5.

Preparations for archaeological surveys include:

• Defining the APE or Study Area on project mapping.
• Researching appropriate records and literature.
• Identifying Native American concerns.
• Securing the required permits for the survey from public agencies and private landowners.
• Scheduling the survey and making physical arrangements(coordinated with District Right of Way).

The archaeological survey area is based on the project APE, set by the Project Manager and the Caltrans PQS, see

Chapter 4, Section 4-3

If the APE has not been set by the time an archaeological survey is needed, then a Study Area will be designated until an APE can be delineated. The APE for archaeology is referred to as the Direct APE. It usually includes the existing right of way; any new right of way; all proposed easements, temporary or permanent, including staging areas or construction access roads; and material or disposal sites that may be impacted by project activities.

The project map, either a contour map or an aerial photograph, should have the project APE or Study Area delineated on it by District personnel in consultation with the Project Manager. Depending on the complexity of the project, all major cultural features and all facets of the proposed project (e.g., cut/fill lines, drainage structures, new right of way, borrow sites, haul roads) should be depicted on the map.

Accurate maps or aerial photographs allow the archaeologist to plan the archaeological field survey, compare the project limits to the results of positive records searches, plot archaeological sites in relation to the proposed project, and ensure that the entire APE or Study Area is surveyed. In preparing for fieldwork on projects requiring new right of way, District Right of Way (R/W) personnel contact the landowners of private parcels through which the survey will pass.

Some background research is always conducted in advance of archaeological field surveys to ensure that surveyors are adequately informed about the types of resources they may be required to identify in the field. Staff should complete some minimal background research for all projects that require cultural resource identification efforts, as discussed in Chapter 4,

Section 4-5

and

Exhibit 4.1

The CHRIS Information Centers maintain records and reports of survey and excavation projects and are to be consulted prior to field survey and as early as practicable in the project planning process. Consult Caltrans records, such as previous studies and as-built drawings, prior to going in the field. Additional research may be appropriate for particularly sensitive regions or in urban settings.

Archaeologists typically request a CHRIS records search that identifies previously recorded sites and surveys within a one-mile radius of the study area and obtain copies of records for all recorded resources within one-quarter mile. Archaeologists should keep in mind the setting and scope of the undertaking when determining the appropriate spatial distance for the records search. For example, for an undertaking on a river, look for sites up and down the river rather than in a simple arbitrary circle. Where previously recorded archaeological sites are identified during the records search, that information should be used to predict archaeological sensitivity of the undertaking’s APE. If a site was previously recorded in the undertaking’s APE, include the previous site record form and updates in the ASR.

A CHRIS records search may be necessary to acquire enough information to screen an undertaking out of the Section 106 review process according to

Section 106 PA Attachment 2

and procedures in

Section 4-2.1

Consult with the CCSO Section 106/PA Coordination Branch (Section 106 Branch) Chief if additional guidance is necessary.

The project archaeologist works with the District Native American Coordinator (DNAC) to contact the appropriate Native American Tribes, groups or individuals to solicit any concerns they have about the proposed project or information they have on cultural resources in the project area.

This section provides specific guidance regarding archaeological field survey methods and the preparation of Archaeological Survey Reports (ASR). In practice, an archaeological survey is always conducted unless it can be shown that

• All ground surfaces have undergone substantial modern disturbance, or
• The PQS determines that the APE or Study Area has been previously surveyed to appropriate standards.

The purpose of the archaeological survey is to identify and record all resources that meet the National Register of Historic Places National Register) definition of a “site” (See National Register Bulletin 16A: Appendix IV). The archaeologist also may make note of any historic-era built resources or other properties, such as potential Traditional Cultural Properties that may require referral to other experts.

According to Caltrans policy, nearly all ground-disturbing projects are surveyed in the field for the presence of archaeological resources. This includes projects in areas that may be rated as having "low archaeological sensitivity" by other agencies such as Information Centers. Saving a small amount of time by not surveying in low-sensitivity areas does not offset the risk of later delaying a project when there is late discovery of archaeological resources in such areas.

Archaeologists should survey plowed fields and graded areas because undisturbed portions of sites may still exist within those areas. In some urban areas, where no original ground surface is exposed, archaeologists should still conduct background research to determine whether:

1)      Previously recorded sites are known, and

2)      To identify the potential for buried sites that may require identification measures beyond a pedestrian archaeological reconnaissance.

If there is a high expectation for buried sites, subsurface testing or remote sensing studies might be warranted as part of the identification effort. Some projects do not require archaeological surveys. The most straightforward case for not conducting a survey is when adequate surveys in the area previously have been completed. An archaeological survey may not be necessary in urban areas where research shows no original ground surface remains; however, the identification effort should assess the potential to encounter subsurface archaeological deposits. If a survey is not performed, the archaeologist should document the reasons in a memo that will be placed in the project file and, if appropriate, attached to the HPSR.

Field Methods

Collection of Artifacts

Section 106 PA Attachment 4 identifies certain specific classes of properties that typically do not require recordation, evaluation, or further review. Chapter 4, Section 4-4.1 discusses the procedures for implementing Section 106 PA Attachment 4. The lead surveyor is authorized to determine, in the field, what archaeological resources need to be recorded. Before fieldwork, the appropriately qualified PQS should define what constitutes an isolate, as this may vary from region to region and may differ from OHP's definition of "less than three associated artifacts." Isolates are formally recorded only under unusual circumstances or for exceptional finds, such as a fluted projectile point. Some public land-holding agencies, as part of their use permits, may require archaeologists to record isolates on their lands.

Section 106 PA Attachment 4 includes the category “isolated prehistoric finds consisting of fewer than three items per 100 m².” When potential isolated prehistoric finds are encountered, care should be taken to ensure such finds are in fact isolated. At the lead surveyor’s discretion, shovel scrapes may be employed. The ASR should discuss all identification methods used.

Section 106 PA Attachment 4 also includes the category “isolated refuse dumps and scatters over 50 years old that lack specific associations.” This property type may require some research but typically does not warrant recordation, or evaluation effort. In situations where the potential for historical association (or lack thereof) is not directly evident, contact a Caltrans PQS for historical archaeology to discuss the property.

The level of documentation afforded exempt properties is based on the professional judgment of the PQS, in accordance with the guidance provided in Section 106 PA Attachment 4. Documentation, if warranted, should be “…at a level commensurate with the nature of the property.”

It may be appropriate to note such finds in the ASR and on coverage maps in technical survey documents, but they are not described in the HPSR and are not plotted on APE maps. More formal recordation (e.g. DPR primary record forms) should be used sparingly, as resources that warrant this level of documentation may require formal evaluation. Section 106 PA Attachment 4 does not apply to “…archeological sites, traditional cultural properties, or other cultural remains or features that may qualify as contributing elements of districts or landscapes.”

The key to successful implementation of Section 106 PA Attachment 4 is sound professional judgment. Contact the appropriate CCSO Branch Chief with questions concerning the applicability of this Attachment to specific resources.

Surveyors should look for all evidence of past occupation, but recordation efforts should be restricted to resources that meet the definition given for prehistoric and historical archaeological sites. Archaeological properties not meeting the criteria of Section PA Attachment 4 should be recorded, included in the ASR and referred to an appropriately qualified Principal Investigator for evaluation, as warranted. Prehistoric and historical archaeological sites should be recorded in detail using the DPR 523 forms. Instructions for completing the DPR 523 series forms are contained in the Office of Historic Preservation's Instructions for Recording Historical Resources (1995). DPR 523 Forms tailored for Caltrans use can be found on the DEA website under “Cultural Resources Studies, Cultural Resources Issues” in the DPR 523 Form Templates section.

The specific kinds of forms used to record a property will depend on the nature of the project and the type and complexity of the resource. The minimum level of documentation for all cultural resources is a Primary Record (DPR 523A) and Location Map (DPR 523J).

Detailed recordation of archaeological sites should minimally consist of:

• Primary Record (DPR 523A).
• Archaeological Site Record (DPR 523C).
• Sketch Map (DPR 523K).
• Location Map (DPR 523J).

If the following types of features are present, recordation also may require the use of:

• Rock Art Record (DPR 523G).
• Milling Station Record (DPR 523F).
• Linear Feature Record (DPR 523E).

Very large and complex sites composed of multiple components or features could also be recorded as districts. Use a Primary Record, Location Map, and District Record (DPR 523D) to document districts, with individual records also prepared for each major contributing element that falls within the APE of a project. Minor elements of the district usually do not require individual records if they can be described adequately on the District Record.

The documentation of historical archaeological resources that include linear features should be supplemented with a Linear Feature Record (DPR 523E) for the ruins of linear structures (e.g., water conveyance system, railroads, trails, and road ruins). Reasonable efforts should be made to ascertain the entire extent of any linear resource that is documented, using records such as historic maps and aerial photographs or inspection points at easily accessible locations along the resource. Summarize the information about the entire resource, to the extent known, on a Primary Record and Location Map. On the Linear Resources Record, mark the detailed field documentation of the portion of the resource within the APE or Study Area, as well as any other inspection points.

When recording prehistoric and historical archaeological sites the following considerations apply:

• If practicable, the entire property should be recorded, even when portions of that resource fall outside the initial Study Area. Under those circumstances it may be appropriate to expand the Study Area. For very large and complex resources (e.g., districts and linear resources) it may be adequate to define the overall extent and general configuration of the property without recording features outside the Study Area in detail. The final APE would then encompass the boundaries of the identified properties.
• For the purposes of field recordation, site boundaries should be drawn as lines encompassing all of the associated physical remains. Historical information should be used to the fullest extent possible when defining the limits of historic-era resources. Information about parcel, claim, and easement boundaries may have bearing on the limits of a historical resource.
• It is not necessary to describe every item observed, but a representative sample of the various types of materials present at a resource should be provided. Some effort should be made to describe, and, where appropriate, illustrate or photograph diagnostic materials such as projectile points, beads, and marked historic-period artifacts. For resources with multiple features or activity areas, observations regarding associated cultural materials should be given separately for each recorded locus because those locations may differ in age or function.
• As appropriate, describe the building materials and construction techniques of built environment ruins. Qualified historical archaeologists, architectural historians, or historians can assist with describing these ruins.
• Record all observable ground disturbances in and adjacent to archaeological deposits, including subsequent construction of buildings or roads. Plot all disturbance and modern features present at the site on the sketch map.

It is Caltrans policy that statements of significance regarding a site’s eligibility for inclusion in the National Register and California Register of Historical Resources (California Register) are not made solely on the basis of site record information. Evaluations are the result of field visits and more extensive studies by appropriately qualified archaeologists.

Use the Archaeological Survey Report (ASR) to document archaeological survey results. Be sure to append copies of all previously and newly prepared site records to the ASR. Exhibit 5.1 contains guidelines for the format and content of ASRs. The ASR documents both positive and negative archaeological survey results; it does not evaluate sites.

The ASR demonstrates that Caltrans has made a reasonable level of effort to identify historic properties that is commensurate with the scale and scope of the undertaking. Accordingly, the level of detail included in the ASR is variable. A small project with no sites may result in a three-page ASR while a large project through several ethnographic areas with a number of sites may result in a 50-page ASR.

The ASR should briefly discuss the results of background research, including the modern environment, paleoenvironment, archaeology, ethnography, and history of the study region as appropriate. These background sections serve to provide a context for understanding the sites identified in the study, the project area sensitivity, and appropriate identification methods. Do not include irrelevant or unnecessarily detailed information in the report. In the text, the ASR should briefly describe and discuss each recorded resource individually. Do not include specific recommendations for further work in the ASR. If recommendations are to be made, the archaeologist should include them in a memorandum transmitting the final ASR to the DEBC.

When to Use a Supplemental ASR

Maps

Peer review of ASR

Approval and Distribution of ASR

The Extended Phase I (XPI) study is an extension of the identification phase, meeting the requirements of 36 CFR §800.4(b) and Section 106 PA Stipulation VIII B "to identify historic properties within the area of potential effects" and similar requirements under CEQA. The chief goal of the XPI study is to define part or all of the boundaries (horizontal or vertical) of an archaeological site. According to FHWA, SHPO and Caltrans policies, there are five reasons to conduct an XPI study:

1)      To determine whether a portion of a site extends horizontally into areas potentially affected by the undertaking, which would necessitate inclusion of the entire site within the undertaking’s APE.

2)      If site deposits do extend into areas potentially affected by the undertaking, to determine whether the deposits also extend into the Direct APE, or can be fully protected with the use of an Environmentally Sensitive Area (ESA).

3)      If site deposits do exist within the Direct APE, to determine whether the portion of the site within the Direct APE is so disturbed that it would no longer have a potential to contribute to National Register eligibility or CEQA significance for the site as a whole.

4)      To determine if a subsurface deposit is associated with surface materials or features (such as a bedrock milling station with no apparent associated remains).

5)      To search for archaeological deposits (as an extension of the survey effort) in areas of high sensitivity where such deposits may be buried or obscured by sediment deposition, vegetation, or landscaping or other modern development.

This type of study is not appropriate if surface indications suggest a reasonable likelihood that an undisturbed or minimally disturbed subsurface deposit does exist in the APE.

The XPI study includes:

• Preparation of a proposal.
• Fieldwork.
• Laboratory work.
• Preparation of a report on the study results.

The results are summarized in the HPSR for federal undertakings or HRCR for state-only projects, to which the XPI Report is appended.

The typical work effort for fieldwork and reporting of an XPI study is 360 hours. The average elapsed time for producing a final product is 180 calendar days (6 months).

Caltrans PQS archaeologists prepare and peer review an Extended Phase I (XPI) Proposal, and the DEBC approves it, prior to excavations. The proposal should indicate the reasons for the XPI study, the field methods to be used, and the thresholds that will determine when the study goals have been met. Because of the limited scope of the XPI study, extensive background information, and elaborate discussions of regional research questions are not appropriate.

The XPI proposal also should include:

• Curation plans.
• Arrangements for a Native American Monitor.
• Estimates of the time and personnel required to complete field, laboratory, and reporting tasks.

Proposal length should not exceed a few pages. Exhibit 5.2 provides guidelines for preparing the XPI proposal.

Methods of excavation for this phase of study may include any combination of standard archaeological techniques, including mechanical excavation, surface scrapes, auger holes, shovel test pits, rapid recovery units, standard control units, and trenching. The XPI proposal should explain how the specific methods selected, including the type, number, and placement of study units, will achieve the study's goals.

Peer Review of XPI Proposal

Approval and Distribution of XPI Proposal

Pre-field preparations include:

• Obtaining maps and/or aerial photographs.
• Securing permits and curation agreements.
• Coordinating with Native American Monitors.

The Pre-excavation Checklist (Exhibit 5.9) contains additional pre-field preparations.

Maps and/or aerial photographs of sufficient detail are necessary to document the XPI fieldwork and to show the relationship of site limits to the project APE.

Assessor’s parcel maps should be obtained in order to clearly determine the ownership of the property on which excavation is to be undertaken. Engineering plans, cross-section schematics, and/or as-builts may be necessary to determine and demonstrate the spatial relationship between proposed testing efforts, previous disturbances, and the proposed project.

For liability reasons, written permission from private landowners is necessary if the fieldwork is conducted on private land. The project archaeologist will supply to District Right-of-Way staff a concise and clear written explanation of the work to be conducted. Artifacts legally are the property of the landowner and are to be returned to the owner, unless a written agreement is obtained for Caltrans to retain and curate the recovered artifacts. Professional responsibilities dictate that every effort should be made to obtain permission for curation of recovered archaeological materials. Section 5-11 discusses permit requirements, procedures, and responsibilities; Exhibit 2.6 also contains additional guidance on obtaining entry.

A curation agreement with an approved facility should be in place before fieldwork commences. If arrangements with a facility cannot be completed prior to work, the proposal must identify how and where materials will be maintained until an agreement is reached. The DEBC reviews and approves the curation agreement.

The project archaeologist works with the DNAC to notify the appropriate Native American Tribe, group, or individuals and provide them the opportunity to participate in the XPI study.

The minimum qualification for directing the XPI study is Co-Principal Investigator under the supervision of a Principal Investigator; qualifications levels for other participants in the XPI are shown in Exhibit 1.5 Table 2.

Field and laboratory work should follow the proposed plan. Because XPI studies typically result in the recovery of a minimal quantity of archaeological materials, laboratory work will probably be limited to washing, basic identification of materials and artifact types, cataloging the materials, and the tabulation of their quantities.

If a Phase II study is to be undertaken soon after the XPI fieldwork, the full processing and analysis of the XPI collection may be deferred for inclusion with the Phase II collection. However, if any uncertainty exists as to whether the Phase II study will be conducted, or if any substantial time will elapse before it is begun, the XPI collection separately should be processed and reported. Caltrans is committed to complete documentation of the collection, regardless of changes in highway project plans.

Recovered materials are to be curated at an appropriate repository in accordance with 36 CFR Part 79, “Curation Of Federally Owned And Administered Archaeological Collections”, and OHP’s “Guidance for the Curation of Archaeological Collections”.

Remote Sensing

Fieldwork also may include remote sensing. Information gained through remote sensing may aid in the identification and National Register eligibility and CEQA significance evaluation of a site by gathering context-related data on subsurface components through non-invasive means. This option is true in depositional and non-depositional environments. Exhibit 5.10 contains a more complete discussion of the benefits and requirements for incorporating a remote sensing survey into project schedules.

The Extended Phase I (XPI) Report explicitly should address the purpose for which the work was undertaken: the relationship of the site limits to the project's direct and indirect APE, and the integrity of the deposit within the direct APE. If the study has refined the boundaries or characteristics of the archaeological site, append a revised archaeological site record to the report. Additionally, the report provides basic documentation of any cultural materials that were recovered and the nature of the deposits that were encountered.

Do not include recommendations for further work in the XPI Report. Include such recommendations, if there are any, in the transmittal memo attached to the final report sent to the DEBC for approval. Exhibit 5.3 provides guidance for the format and content of XPI Reports.

Peer Review of XPI Report

Approval and Distribution of XPI Report

Federal agencies are required to follow 36 CFR §800 to consider the effects of an agency's undertaking on properties listed in or determined eligible for inclusion in the National Register, and to afford the Advisory Council on Historic Preservation (ACHP) a reasonable opportunity to comment on the effect finding. Caltrans achieves this for FHWA through implementation of the Section 106 PA. For sites that cannot be avoided by the project, CEQA Guidelines §15064.5 also provide for the evaluation of their importance and CEQA Guidelines §15126.4(b) provide for mitigating project effects to important sites.

Caltrans uses the National Register criteria (36 CFR §60.4) to evaluate whether a site is eligible for inclusion in the National Register for Section 106 compliance on federal undertakings, as well as for compliance under Public Resources Code (PRC) §5024 for state-owned archaeological resources. For CEQA, Caltrans uses the California Register criteria (PRC §5024.1), as required by CEQA Guidelines §15064.5(a)(l). See Exhibits 2.16 and 4.2 for additional information on eligibility criteria.

If project impacts to an archaeological site cannot be avoided, a Phase II study may be undertaken to evaluate the site and to assess potential project effects. A Phase II study may consist of test excavations and other work for these objectives. The results of a Phase II study are presented in an Archaeological Evaluation Report (AER), which is appended to an HPSR or HRCR, per Section 5-6.8 below.

Archaeological sites are most commonly determined eligible for inclusion in the National Register based on Criterion D because they "have yielded or may be likely to yield information important in prehistory or history." In some cases, other National Register criteria may apply to archaeological sites as well. However, in order to be eligible under these other criteria, a property must also retain integrity (see Exhibits 2.16, 4.2 and National Register Bulletin 15 for more detailed discussions of integrity).

Archaeological sites may qualify for the National Register by criteria or characteristics other than those that effectively can be obtained or mitigated by excavation. These National Register qualities may necessitate preserving the site in place and, thus, may subject the site to Section 4(f) of the Department of Transportation Act of 1966 (see Chapter 2 for further discussion of Section 4[f]).

On projects with a high number of prehistoric archaeological sites or prehistoric archaeological sites of a sensitive nature, it may be appropriate to conduct a formal ethnographic study of the project area. Such a study would determine if other cultural attributes associated with the sites could contribute to significance, perhaps with reference to National Register eligibility criteria other than Criterion D. This type of study should be viewed as complementing, rather than replacing, the larger Native American consultation effort for a project (see Chapter 3). Such studies might consist of ethnographic and historic research and interviews with Native American informants. Studies of this type should be conducted concurrently with archaeological investigations and integrated or attached to the body of the Phase II report, as they may enhance one’s understanding not only of the National Register status of the sites, but also of the archaeological data gathered during Phase II excavations.

Phase II Study

5-6.1 Assumption of Eligibility

Prehistoric archaeological sites usually require test excavation to determine whether they qualify for inclusion in the National Register. However, there are cases in which a determination can be made without Phase II excavation.

A site may be determined to be eligible for inclusion in the National Register on the basis of:

• Information generated in previous excavations.
• Unusual and important surface characteristics, such as rock art, or features such as house pits.
• Ethnographic or ethnohistoric information.
• Existing stratigraphic exposures indicating the presence of important subsurface constituents.

In unusual circumstances, a site may be determined ineligible without subsurface testing, based on depositional circumstances that preclude the presence of any subsurface cultural deposit. Examples of this type of circumstance include an isolated bedrock-milling feature on an expanse of granite bedrock, or when research clearly shows a loss of integrity because of previous construction impacts.

The basis for a conclusion that a site is eligible or not eligible for inclusion in the National Register without subsurface testing must be thoroughly and convincingly documented. Caltrans does not have a report type specifically for this situation. In most cases, use of a modified Archaeological Evaluation Report format will be appropriate. In simple cases, however, a letter report may suffice; see Exhibit 6.1. Note that under Criterion D, sites may be eligible based upon their potential to yield information. This potential must be explicated clearly, based on a fully developed research design and an understanding of similar site types. A Principal Investigator (prehistoric or historical, as appropriate) must prepare and sign the document, which needs to be peer reviewed by a similarly qualified archaeologist. It will be attached to the HPSR or HRCR.

There are both potential advantages and disadvantages in evaluating eligibility without excavation. Omitting a Phase II study may substantially reduce costs and schedule time. It may eliminate disturbances to portions of a site that will not be affected by the highway project. However, if the proposed eligibility determination is not accepted by reviewing agencies, and test excavations are ultimately required, the adverse consequences for the project's schedule may be severe. Test excavations also help in evaluating project effects and in designing appropriate data recovery programs. These objectives may be more difficult to meet if Phase II test excavation is bypassed.

Some Phase II studies may be accomplished through resource-specific programmatic treatments developed and coordinated by the OHP. These programmatic treatments, called CARIDAPS or California Archaeological Resource Identification and Data Acquisition Programs, establish procedures for the efficient identification, recordation, and management of certain archaeological resource classes that contain limited but useful data. The Sparse Lithic Scatter CARIDAP is the only CARIDAP that OHP has approved to date.

The implementation of a CARIDAP serves to satisfy the historic compliance process and is meant to streamline the management process by eliminating the need for formal Phase II or Phase III studies. For a qualifying site, CARIDAP implementation defines the site through prescribed field identification methods, and provides sufficient information to ensure accurate site classification and evaluation of the resource’s research potential. For this CARIDAP to be applicable, the site must meet the following criteria:

1)      It must contain only flaked stone, and lack other classes of archaeological material (such as groundstone, fire-affected rock, pottery, bone, or shell).

2)      It must be smaller than 10,000 m² in area.

3)      It must lack a substantial cultural deposit, as defined by the program.

4)      It must have surface artifact densities less than or equal to three items per square meter.

The restrictions of these criteria (especially #1 and #3) limit the applicability of the CARIDAP program in evaluating most sites. CARIDAP treatment is also not appropriate when only a portion of the site is accessible.

Experience has shown that the CARIDAP process often reveals the need for a more traditional and complete Phase II evaluation. Thus, while the CARIDAP is designed to streamline the evaluation process, the risk of having to do an additional Phase II study, with attendant costs and schedule delays, is a significant drawback in using the CARIDAP program. For this reason, the CARIDAP program may be most useful as an initial stage in a larger evaluation effort. In this case, the Phase II proposal/research design should address the use of this program.

Use of the CARIDAP in this fashion allows for evaluation efforts to be abbreviated, if CARIDAP criteria are met. If the CARIDAP criteria are exceeded, it allows for full evaluation efforts to proceed in accordance with the research design.

An Archaeological Evaluation Proposal (AEP), previously referred to as a “Phase II Proposal,” is prepared and peer-reviewed by qualified prehistoric archaeologists and approved by the DEBC prior to excavations. The proposal should state the goals of the study, and clearly link the anticipated field and laboratory work to those goals. Exhibit 5.4 provides guidelines for preparing the proposal.

Because a Phase II study will evaluate the research potential of a site, the proposal must present:

• Sufficient background information.
• A realistic and site-specific research design.
• Discussion of relevant regional research issues.

Arrangements for Native American Monitors, curation plans, permits and estimated time and personnel requirements are also addressed. District Caltrans PQS also should inform the project biologist of the proposed testing activities to ensure that an archaeological excavation would not result in impacts to significant biological resources.

Peer Review of AEP

Approval and Distribution of AEP

The following are key pre-field preparations:

1. Obtain the necessary project maps, aerial photographs, assessor’s parcel maps, etc.
2. Secure the proper permission or permits and curation agreements.
3. Coordinate with the Native American community and specifically with the Native American Monitor.

Additional pre-field measures may be found in the Pre-Excavation Checklist provided as Exhibit 5.9.

Obtain the appropriate maps or aerial photographs from the project engineers or through the District or Headquarters Photogrammetry units. The Environmental Planner (Generalist) for the project typically obtains the Assessor’s parcel maps.

The Principal Investigator confirms that the proper permits are secured if the study will occur on, federal, or other public lands, or within the coastal zone. The timeframe for pre-field preparations must allow for the permit processing. See Section 5-10 for an expanded discussion on permit requirements, procedures, and responsibilities

Assessor’s parcel maps should be obtained in order to clearly determine the ownership of the property on which excavation is to be undertaken. Engineering plans, cross-section s